“First, you find the stars that make the W,” he told her, repeating what I’d said. “Can you see them?”

“Yes,” she said after a moment.

“That’s . . .” Again Keaton looked at me.

“Cassiopeia,” I said.

“Cassiopeia,” he echoed, his breath thick and white in the frigid night air. “Now look below the left part of the zig-zag. Can you see a cluster of stars there?”

“I think so. Is that Perseus?”

“Yes. Henry was just telling me the story. Did you know that constellations have stories?”

“Yes, but I don’t know many of them.” Sylvia straightened up and let her son look through the telescope again. Shivering in the cold, she turned to me. “What’s the story of Perseus?”

I wanted so badly to put my arms around her and warm her up, but I stayed a respectable three feet away. “Well, I’m probably not remembering every detail exactly right, but Perseus was the grandson of a Greek king who’d been told his grandson was going to kill him. So to prevent a grandson from even being born, he locked his own daughter up in a tower.”

“Always the tower,” she said with a sigh.

“Don’t worry. Zeus fell in love with her and visited her in the form of, um”—I glanced at Keaton—“golden rain. Which falls into her lap and causes her to get pregnant.”

Sylvia laughed. “Go on.”

“So the king is really mad about the baby and locks them both in a trunk, then throws the trunk out to sea.”

Sylvia gave Keaton a swat on the behind. “Remember this when you think I’m being too harsh.”

I grinned. “Then Zeus rescues them and they end up on this island for years, where someone—and I can’t even remember who or why—tells teenage Perseus he has to go bring back Medusa’s head.”

“Is she the one with snakes for hair?” Keaton asked.

“That’s right. So no one actually thinks Perseus will be able to do it, but he does, and along the way he also falls in love with this beautiful girl named Andromeda. She was chained to a rock and left to die by her parents.”

“Sheesh, this story is making me feel infinitely better about my parenting skills.” Sylvia smiled at me. “Tell me there’s a happy ending.”

“There is. Perseus brings Andromeda home and they get married and have lots of children. Her constellation is next to his in the sky.”

“Awww, I like that.” Sylvia glanced up at the star-studded winter sky. “So he didn’t kill his grandfather?”

“Oh yeah, he did. But that was more of an accident.”

She laughed and shook her head. “I’ll focus on the happily ever after part. But I’m freezing out here. Are you guys coming in?”

“Can I have a few more minutes?” Keaton begged. “I want to try to find the comet.”